Why does the idea of a knob of sweetly melting butter on top of a juicy steak seem so decadent to me? They are two products from the same animal, after all. It is a little indulgent, and it’s one of the most delicious combinations I can think of.

I eat it infrequently, but when I’m craving grilled meat I need a steak. The flat iron is one of my favorite cuts; it’s way more affordable than my top pick, a rib-eye, and it comes from the beef chuck so it has great flavor. It’s also a nicely uniform size, which makes it perfect for slicing and piling into a sandwich.

I made a compound butter for this sandwich to fancy it up a little. The flavor reminds me of a classic Steak Béarnaise sauce, with lemon juice and pickles supplying the familiar tang along with some fresh tarragon.